I Have two old karaoke machines that I picked up from a garage sale for 10$. I want to hook these two karaoke machines together so they play as one system. However it seems they only have input jacks on the back and no output. One has an rca jack for input and the other has an aux input. I tested both inputs with an ipod plugged in and they work fine. How ever I can't think of a way for them to work together. Would like them to play music and both work with a mocrophone if possible! So if you have an idea or need more info, comment! Thank you.